Method and system for facilitating voice mail service in a communication network through data-publication by a signaling server

ABSTRACT

A mechanism is disclosed for facilitating the performance of communication services in a communication network. An enhanced proxy server receives and proxies to a voice mail server a message indicative of a call attempt from an originating party to a terminating party. Further, the enhanced proxy server extracts an outgoing voice mail message from a data store and makes the outgoing voice mail message available for the voice mail server to play to the originating party in a session established between the voice mail server and the originating party in response to the signaling message.

REFERENCE TO RELATED APPLICATION

This is a continuation of U.S. patent application Ser. No. 10/071,833,filed on Feb. 7, 2002, the entirety of which is hereby incorporated byreference.

BACKGROUND

1. Field of the Invention

The present invention relates to network communications and moreparticularly to facilitating services in a communication network.

2. Description of Related Art

As a general matter, it is known to provide services for subscribersover communication networks. By way of example, and without limitation,three such services are (i) establishing a “push-to-talk” session for arequesting party, (ii) multicasting an instant message from aninitiating party to a defined group of other parties, and (iii)providing voice mail service for unavailable parties. Many otherservices exist as well or will be developed in the future, but thesethree services will be used as examples throughout this description.Therefore, example arrangements and operation of each of these serviceswill first be described briefly here.

a. Initiating a Push to Talk Session

“Push-to-talk” (PTT) service, as it has come to be known, involvesestablishing an “instant” communication session between two or moreparties over a communication network. (Note that PTT does not literallyprovide for “instant” (i.e., immediate) session establishment; however,the session establishment is sometimes considered “instant” in the sensethat a very quick connection is usually established between theparticipating parties. Note also that PTT service normally concernsvoice communications; but the “PTT” concept extends equally tocommunication of other media, such as video for instance.)

Generally, to establish such a session, a PTT server on a networkestablishes and bridges together communication legs among a plurality ofusers. To facilitate this, a PTT server normally maintains agroup-database or registry that indicates groups of users who aredesignated to communicate with each other.

When a user wants to initiate a PTT session, the user sends aninitiation request to the PTT server. In response, the PTT server refersto the group-database to identify members of that user's group (alsoreferred to as the user's “buddies”). And the PTT server establishes acommunication leg with the initiating user and respective communicationlegs with each identified member of the user's group and bridges thoselegs together so that they can communicate with each other.

PTT service is particularly well suited for wireless communications,especially where users employ wireless handsets (mobile stations) thatare able to engage in packet-data communications. Under current industrystandards, for instance, a “3G” mobile station can communicate over anair interface with a base transceiver station (BTS) and in turn with abase station controller (BSC). For conventional “voice” communications,the BSC is then linked with a mobile switching center, which providesconnectivity to the public switched telephone network (PSTN). Further,for data communications, the BSC is also linked with a packet dataserving node (PDSN), which provides connectivity with a packet-switchednetwork such as the Internet. (In later generation wireless networks,the BTS and/or BSC may themselves sit as nodes on a packet-switchednetwork, providing more of an end-to-end packet-based solution.)

A 3G mobile station then typically includes logic to digitize, encodeand packetize voice and/or other media and to send the resulting packetsover a point-to-point protocol (PPP) channel to the PDSN fortransmission in turn over the packet-switched network. Similarly, themobile station includes logic to receive packets over the PPP channelfrom the packet-switched network, and to depacketize and recover theunderlying media and to play out the media to a user. Thus, a 3G mobilestation, like a multi-media personal computer, can allow a user toengage in media-over-IP (e.g., voice-over-IP (VoIP)) communications.

To facilitate PTT service, a mobile station can be programmed with a PTTapplication, which, when invoked by a user, would cause a PTTinitiation-signal to be sent into the network for transmission to a PTTserver. The initiation signal can take any of a variety of forms. By wayof example, it may be an “INVITE” request message pursuant to theindustry standard session initiation protocol (SIP). According to SIP, auser-agent module on the mobile station would generate the INVITE andsend the INVITE to a proxy server on the network. The INVITE mightindicate generally a request for the user to engage in a PTT session.Conventionally, the SIP proxy server would then forward or “proxy” theINVITE to a suitable PTT server.

Upon receipt of the INVITE, the PTT server would then query its groupdatabase to identify members of the user's group and might then engagein SIP signaling to set up communication sessions (conference legs) witheach member and with the initiating user. After setting up each leg, thePTT server would then bridge them together so that the parties cancommunicate with each other. This entire setup process might occur in amatter of milliseconds. Therefore, from the user perspective, theprocess can appear instantaneous.

b. Multicasting an Instant Message

Instant messaging (IM) service involves quickly communicating a messagefrom a user's communication terminal to one or more other users. IMservices can operate in any of a variety of ways.

As a general matter, to facilitate IM service, an IM server on a networkwill receive subscriptions from users requesting to be notified whenother users are online and available to receive instant messages. When auser goes online, the user may send a registration message to the IMserver, indicating to the IM server that the user is online andavailable. Thus, when the IM server receives a registration messageindicating online status of a user as to whom another user hassubscribed to be notified, the IM server may then notify the subscribinguser accordingly.

With this arrangement, an IM user may then send an instant message toone or more other users that the sender knows are available to receivethe message. According to SIP, the sending user can do this by sending aSIP “MESSAGE” to each designated other user. More particularly, thesending user would send the MESSAGE to a SIP proxy server, designatingthe recipient's SIP ID in the MESSAGE. The proxy server would then proxythe MESSAGE to the network address of that recipient SIP user.

To multicast an instant message to a designated group of recipients, auser might send the instant message to the IM server, and the IM servermight then forward the message to members of the sender's group. As withPTT service, an IM server may thus normally maintain a group-database,which indicates groups of users who are designated to receive multicastinstant messages (or other sorts of messages, for that matter) from eachother or from particular users. And the IM server may refer to thegroup-database to determine endpoint destinations of an instant message.

Continuing with SIP as the example signaling protocol, for instance, aSIP user may send an instant message as a SIP MESSAGE to a proxy serveron the network. The MESSAGE might indicate generally a request to sendthe message to the user's group. In response, the SIP proxy might thenproxy the MESSAGE to the IM server. Upon receipt of the MESSAGE, the IMserver may then query its group-database to identify members of thesender's group, and the IM server may then send the MESSAGE respectivelyto each available member of the group.

c. Providing Voice Mail Service

Voice mail service is exceptionally well known. Generally, when aninitiating party attempts to establish a communication with aterminating party and the terminating party is unavailable, a networkentity may instead establish a communication session between theinitiating party and a voice mail server. The voice mail server wouldthen play an outgoing message and receive and record a message from theinitiating party. The voice mail server may then later play the recordedmessage to the terminating party.

SIP can be used to facilitate voice mail service as well. According toSIP, an initiating SIP user would cause an initiating user agent to sendan INVITE to a proxy server, indicating a request to establish acommunication session with a terminating SIP user. The proxy serverwould then forward that INVITE to the network address of the devicewhere the terminating SIP user is located. With SIP, if a user agent atthat terminating address does not then respond to the INVITE by sendinga conventional SIP “200 OK” response message back to the proxy serverwithin a particular time period, the proxy server might then cancel theINVITE to the terminating SIP user agent and instead forward the INVITEto a voice mail server.

Upon receipt of the INVITE, the voice mail server might then respond tothe proxy server with a “200 OK,” which the proxy server would forwardto the initiating user agent. In turn, the initiating user agent wouldthen send a SIP “ACK” message to proxy server, which the proxy serverwould forward to the voice mail server. As a result, a media sessionwould be established between the initiating SIP user and the voice mailserver. Through that media session, the voice mail server would thenplay an outgoing message prompt and would receive and record a messagefor later retrieval by the terminating user. (In this regard, the voicemail server could interact with the caller by applying an interactivevoice response unit (IVRU) or through execution of VXML applications, orin any other way desired.)

SUMMARY

An exemplary embodiment of the present invention is directed to amechanism for facilitating services in a communications network. Inaccordance with the exemplary embodiment, an enhanced proxy server isprovided. The enhanced proxy server includes or has access to a datastore, which includes data that can be used by one or more applicationservers to facilitate carrying out a service in response to a signalingmessage provided by the proxy server.

Generally speaking, after the enhanced proxy server receives a signalingmessage related to a communication, it will send the signaling messagealong its way for receipt and handling by at least one applicationserver. In addition, however, the enhanced proxy server will alsoextract from the data store a set of data (one or more pieces ofinformation) that can be used by that application server to facilitateperformance of a communication service in response to the signalingmessage. And the enhanced proxy server will make that data available foruse by the application server.

In the exemplary arrangement, the signaling message can be a sessioninitiation request message sent by or on behalf of a communicatingentity (user and/or device). (For instance, the signaling message can bea SIP message, such as an INVITE or a MESSAGE.) And the data that theenhanced proxy server extracts from the data store can be datadesignated or established in advance for that communicating party.

By way of example, the signaling message could be a request to establisha group communication session (e.g., a PTT session), and the data couldbe a group-list designated for the communicating entity. The applicationserver could then be a conference server (e.g., a PTT server) and couldrefer to that group list to determine the entities with which toestablish conference legs. And the application server could then set upand bridge together those conference legs.

As another example, the signaling message could be a request by acommunicating entity to send a communication (such as an instantmessage) to a group of users, and the data could similarly be agroup-list designated for the communicating entity. The applicationserver could then be a messaging server (e.g., an IM server) and couldrefer to that group-list to determine the recipients to whom thecommunication should be sent. And the application server could thenmulticast the message to those recipients.

As still another example, the signaling message could be a request toestablish a communication session with a designated terminating entity.After forwarding the signaling message to the terminating entity and notreceiving a response, the enhanced proxy server could then forward thesignaling message instead to a voice mail server as the applicationserver. Further, the data could be an outgoing media message that iscustomized for the originating entity and/or for the terminating entity.The voice mail server may then establish a media session with theoriginating entity and play that customized outgoing media message tothe originating entity as a prompt to request a voice mail message.

The enhanced proxy server can make the data available for use by theapplication server in any of a variety of ways. As an example, theenhanced proxy server could publish the data on a message bus or in adata store accessible by the application server. In turn, theapplication server can access the data from that message bus or datastore. And as another example, the enhanced proxy server could send thedata to the application server either separately from the signalingmessage, or as a supplemental part of (e.g., appended to or embeddedwithin) the signaling message.

These as well as other aspects and advantages of the exemplaryembodiment will become apparent to those of ordinary skill in the art byreading the following detailed description, with reference whereappropriate to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

An exemplary embodiment of the present invention is described hereinwith reference to the drawings, in which:

FIG. 1 is a block diagram depicting a network arrangement in accordancewith the exemplary embodiment;

FIG. 2 is a flow chart depicting functions that can be carried out inthe exemplary arrangement shown in FIG. 1;

FIG. 3 is a block diagram depicting a more particular networkarrangement in accordance with the exemplary embodiment;

FIG. 4 is a flow chart depicting functions that can be carried out insetting up a PTT session in the arrangement shown in FIG. 3;

FIG. 5 is a flow chart depicting functions that can be carried out inmulticasting an instant message in the arrangement shown in FIG. 3; and

FIG. 6 is a flow chart depicting functions that can be carried out inproviding voice mail service in the arrangement shown in FIG. 3.

DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT

Referring to the drawings, FIG. 1 is a simplified block diagram of acommunication system 10 arranged in accordance with an exemplaryembodiment of the present invention. As shown in FIG. 1, system 10includes a communicating entity 12, an enhanced proxy server 14, and anapplication server 16. The communicating entity 12 is showncommunicatively coupled with the enhanced proxy server 14 by a signalinglink 18, and the enhanced proxy server 14 is in turn showncommunicatively coupled by a signaling link 20 with the applicationserver 16. As further shown, enhanced proxy server 14 includes or hasaccess to a data store 22, which includes data that can be used byapplication server 16 to facilitate performance of a communicationservice in response to a signaling message that is proxied by enhancedproxy server 14.

The various elements shown in FIG. 1 can take any of a variety of forms.By way of example, the element designated as communicating entity 12 canrepresent a user (e.g., a subscriber) and/or a communication device thata user would use to engage in communications. The communication device,in turn, could be a landline and/or wireless communication device. Forinstance, it could be a cellular or PCS mobile station, in the form of atelephone or other device equipped with wireless communicationcapability (such as a personal digital assistant or personal computerequipped with a wireless communication module (e.g., PC card orconnected cell phone)). Or it could be a personal computer or other suchentity with a landline network connection. Other examples are alsopossible.

Enhanced proxy server 14 may similarly take various forms. For instance,the enhanced proxy server can be a computer that is programmed withproxy server functionality and with data-publication functionality. Theproxy server functionality would allow the enhanced proxy server toreceive a signaling message indicative of a communication involvingcommunicating entity 12 and to proxy the signaling message to anappropriate destination (possibly through another proxy), such as toapplication server 16. And the data-publication functionality wouldallow the enhanced proxy server to extract from data store 22 (e.g.,through a suitable query) a set of data that can be used by applicationserver 16 to carry out a communication service in response to thesignaling message, and to make that data available for use byapplication server 16.

Application server 16 may also take any of a variety of forms. Forinstance, application server 16 might be a computer that is programmedto perform a service in response to an incoming signaling message andthat is further programmed to obtain data made available by enhancedproxy server 14 and to use that data to facilitate performance of theservice in response to the signaling message.

The particular service (or services) carried out by application server16 can also take any of a variety of forms. Continuing with the examplesintroduced above, for instance, the service might be setting up andfacilitating a group communication session, such as a PTT session, or itmight be to multicast a message, such as an instant message, or it mightbe to prompt for and record a voice mail message. Many other serviceexamples are possible as well or will be developed in the future. Sothese three examples should in no way be viewed as representing the onlypossible services or types of services that could be carried out by theapplication server.

In turn, the links 18 and 20 could also take various forms. In theexemplary embodiment, for instance, both links represent networkconnections, both possibly over a common network (e.g., WLAN or LAN),such as the Internet or an intranet (e.g., a carrier's core IP network).In this arrangement, communicating entity 12, enhanced proxy server 14and application server 16 may each sit as nodes on the common network.Further, data store 22 may also sit as a node on the network or may beincorporated as part of enhanced proxy server 14 or otherwise accessibleby enhanced proxy server 14. On the other hand, links 18 and 20 couldtake other forms as well, such as direct links between the variouselements shown.

Referring next to FIG. 2, a simplified flow chart is provided, toillustrate a set of functions that can be carried out in the arrangementshown in FIG. 1, in accordance with the exemplary embodiment. As shownin FIG. 2, at block 30, a signaling message is sent by or on behalf ofcommunication entity 12 to enhanced proxy server 14. The signalingmessage preferably concerns a communication involving communicatingentity 12. As such, the signaling message might be a session initiationmessage, a mid-session control message, or some other sort of message,whether or not it contains bearer data.

Communicating entity 12 itself might send the signaling message overlink 18 to enhanced proxy server 14. Or, as noted above, some otherentity might send the signaling message to enhanced proxy server 14 onbehalf of communicating entity 12. For instance, although not shown inFIG. 1, a gateway could exist along link 18 somewhere betweencommunicating entity 12 and enhanced proxy server 14 and could functionto send the signaling message to enhanced proxy server 14, concerning acommunication involving entity 12. Such a gateway might be in place in asituation where communicating entity 12 and enhanced proxy server 14 siton disparate types of networks, such as where communication entity 12sits on a circuit-switched network and enhanced proxy server 14 sits ona packet-switched network for instance.

Further, it should be understood that sending or receipt of “a signalingmessage” could equally mean sending or receipt of multiple signalingmessages. For instance, a sequence of signaling messages together mighthave a given meaning and cause a given effect that any one of thesignaling messages alone might not.

At some point after enhanced proxy server 14 has received the signalingmessage, enhanced proxy server 14 performs at least two functions. Itproxies the signaling message along signaling link 20 to applicationserver 16. And it extracts data from data store 22 (or otherwise selectsa set of pertinent data) and makes that data available for use byapplication server 16 to enable application server 16 to carry out aservice in response to the signaling message. Enhanced proxy server 14may perform these functions concurrently or in sequence. For purposes ofexample, FIG. 1 shows the functions performed concurrently.

Thus as depicted at block 32, enhanced proxy server 14 proxies thesignaling message along signaling link 20 to application server 16.Additionally, at block 34, enhanced proxy server 14 refers to data store22 to obtain data that can be used by application server 16 tofacilitate performing a communication service in response to thesignaling message. And, at block 36 (possibly as part of block 32),enhanced proxy server 14 makes that data available for use byapplication server 16. Thereafter, at block 38, application server 16uses the data to facilitate performing a communication service inresponse to the signaling message.

It should be understood that the above and other arrangements describedherein are illustrative only, and other arrangements and other elements(e.g., machines, interfaces, functions, orders of functions, etc.) canbe used instead, additional elements may be provided, and some elementsmay be omitted altogether. Further, as in most telecommunicationsapplications, those skilled in the art will appreciate that many of theelements described herein represent functions or functional entitiesthat may be implemented as discrete components or in conjunction withother components, in any suitable combination and location, and throughhardware, software and/or firmware.

Referring next to FIG. 3, another block diagram is provided, to helpillustrate some of many possible network configurations that could berepresented by the arrangement shown generally in FIG. 1.

FIG. 3 depicts communicating entity 12 as a wireless mobile station (MS)48 (possibly in conjunction with a computer or other terminal (notshown)), which can communicate via a radio access network with entitieson an IP network 50. More particularly, MS 48 communicates over a radiofrequency air interface 52 with a BTS 54, which is coupled in turn witha BSC 56. The BSC is then coupled with a PDSN 58 that providesconnectivity with IP network 50. (Alternatively, as further shown, theBSC may also be coupled with an MSC 60, which is linked with aninterworking function (IWF) 61 that provides connectivity (directly orthrough PDSN 58) with the IP network, and/or the BSC may be linkeddirectly to the IP network (by link 65) and may thereby itself provideconnectivity to the IP network.)

With this arrangement, MS 48 may establish connectivity over airinterface 48 and through BTS 54, BSC 56 and PDSN 58 with IP network 50.Further, MS 48 can establish a data-link layer connection, such as apoint-to-point protocol (PPP) or serial line interface protocol (SLIP)channel with PDSN 58, and can establish a network layer connection so asto engage in packet-data communications over IP network. MS 48 may workto establish these connections automatically upon power up (so as toprovide an “always on” network connection) or in response to userinstruction.

In the exemplary embodiment, MS 48 preferably includes a processor aswell as a set of program instructions stored in memory and executable bythe processor to carry out various functions described herein. Forinstance, an exemplary MS 48 may include a SIP user agent application,which can function to send SIP signaling messages to a designated SIPproxy on IP network 50, for transmission in turn to a desired endpoint,and to receive SIP signaling messages from IP network 50.

Additionally, the MS 48 may include various other client-levelapplications, such as a PTT application for initiating and supportingPTT communications, an IM application for sending and receiving IMcommunications, and a telephony application for engaging in telephonecommunications. Or the MS 48 could be a thin client and can downloadthese sorts of client-level applications (e.g., as Java/J2ME applets)from suitable network servers. When executed by the processor, thesevarious other client-level applications may invoke the SIP user agent oremploy some other signaling process to send into IP network 50 asignaling message that is indicative of a communication involving MS 48or a user of MS 48.

In the exemplary arrangement of FIG. 3, the function of the enhancedproxy server 14 is embodied within a “service agent” platform 62, whichsits on IP network 50 and which includes logic 64 and a data store 66.Logic 64 may take the form of a processor and machine languageinstructions stored in memory and executable by the processor to carryout various function described herein. As noted above, those functionspreferably include (i) a proxy server function and (ii) adata-publication function.

The proxy server function may be encoded in a SIP proxy serverapplication executable by the processor. As such, the service agent mayreceive a SIP message that designates a destination SIP address (e.g., aSIP ID), may then refer to a SIP registry (also possibly resident on theservice agent) to find out where to send the SIP message. In turn, theservice agent may then send the SIP message to that destination point.Continuing with the examples above, for instance, the SIP message mightbe an INVITE or MESSAGE, which, based on the contents of the messageand/or on other factors, the service agent might proxy to an appropriateapplication server, such as PTT server 68, IM server 70 and/or VM server72.

In the exemplary embodiment, MS 48 may be programmed to send some or alloutgoing SIP messages to service agent 62 as a local SIP proxy for MS48. Alternatively, some other mechanism could exist to push SIP messagesto the service agent for handling. For instance, PDSN 58 could beprogrammed to detect that a packet communication from MS 48 is a SIPmessage and to responsively push that packet communication to serviceagent 62.

The data-publication function of the service agent may also take variousforms. Generally speaking, the idea is that the service agent will makedata available for use by an application server, to enable (partially orfully) the application server to carry out a communication service inresponse to a signaling message that the service agent proxies (directlyor indirectly (through another proxy)) to the application server.

To do this, the service agent could add the data into the signalingmessage that it sends (as a proxy server) to the application server, sothat the application server will receive the signaling message togetherwith the data. Alternatively, the service agent could send the data tothe application server in a separate communication over IP network 50.Such a communication can conform with any agreed protocol.

Still alternatively, the service agent could more literally publish thedata in another data store that is accessible by the application server.For example, FIG. 3 depicts a “public store” 74 on IP network 50, towhich the service agent could publish the data and from which anapplication server could read the data. (Note that, while the publicstore is shown outside of service agent 62, the public store couldequally be incorporated as part of service agent 62.) The public storemight be a database or directory to which service agent 62 can writedata and from which the application server has authority to read data.In this regard, the service agent and/or application server could havepartial or full access/permissions, which can be set in any manner nowknown or later developed.

And as another example, the service agent might publish the data on amessage bus that is accessible by the application server. In thisregard, a message bus architecture with which people of ordinary skillin the art are familiar is described in “A Message Bus for LocalCoordination—draft-ietf-mmusic-mbus-transport-06.txt,” published on May30, 2001, by the Multiparty Multimedia Session Control (MMUSIC) workinggroup of the Internet Engineering Task Force. A message bus has theadvantage of providing very quick access to data, similar to cachememory in a personal computer.

In the exemplary embodiment, the data that the service agent makesavailable for use by the application server can be data that theapplication server requires in order to be able to carry out a givencommunication service. For example, if the application server is PTTserver 68 and the communication service is setting up a PTT sessionamong a group, the data could be a group-list for the originating party.Similarly, if the application server is IM server 70 and thecommunication service is multicasting an instant message to a group, thedata could also be a group-list for the sending party.

Alternatively, the data could function to assist the application serverin carrying out the communication service or to somehow qualify ormodify the communication service. For example, if the application serveris PTT server 68, the data could specify the online status orpreferences of any of the group members. If the data indicates that aparticular group member is not online or is currently engaged in anothersession, the PTT server could then act accordingly as it works to set upthe PTT session (or to modify the PTT session, where the signalingmessage that the service agent proxies to it is a mid-session controlsignal, such as a PTT floor control message).

As another example, if the application server is VM server 72 and thecommunication service includes prompting for a message and recording themessage, the VM server might have a default outgoing message that itnormally plays to any calling party. In that case, the data that theservice agent makes available for use by the VM server could be a customoutgoing media message that has been established at least in part forthe calling party and/or for the called party, and the VM server may beprogrammed to responsively use that custom outgoing message instead ofthe default outgoing message.

For instance, if the calling party is John Doe, the custom outgoingmessage could be an audio stream that states “Sorry John, the party youare calling is currently unavailable. Please leave a message after thefollowing tone” and then ends with a custom tone that John Doe hadselected in advance through a suitable web interface.

And as a related example, if the VM server is a VXML-based voice commandplatform, the VM server might have a default VXML application that itexecutes when it receives a call. In that case, the data that theservice agent makes available for use by the VM server could be a customVXML document that is executable by the VM server to cause the VM serverto take certain actions (e.g., actions specific to the calling partyand/or called party). Other examples are possible as well.

In the exemplary embodiment, data store 66 may hold the data that theservice agent will make available for use by the application server. Assuch, data store 66 may normally hold an assortment of data, and theservice agent may extract from the data store a particular set of datato make available in a given instance. For example, the data store mayhold data that is specific to all users or all devices that subscribe toa given carrier as well as variations of data suitable for use byassorted different application servers and in a variety of differentscenarios.

When service agent 62 proxies (or will proxy) a signaling message to anapplication server, the service agent may query the data store to obtaina set of pertinent data that it should make available. The query can bekeyed to any of a variety of factors, examples of which include (i) theidentity of the communicating entity 12, (ii) the contents of thesignaling message, such as the type of communication at issue, (iii) theidentity or type of the application server, (iv) the identity or type ofservice that the application server will perform, and (iv) the currenttime/date. Many other examples are possible as well.

For example, data store 66 could hold a table that lists authorizedcommunicating entities (e.g., users and devices). And the data storecould hold another table that specifies buddy lists per communicatingentity. And still further, the data store could hold another table thatpoints to stored media files usable as outgoing messages by a VM server.Additionally, the data store could hold another table that specifies ina given instance (e.g., for a given communicating entity, applicationserver, communication service, etc.) which data from the other tablesthe service agent should make available for use by the applicationserver.

In the exemplary embodiment, the data in data store 66 could be updatedregularly, or in response to some triggering event (such as an add,delete or modify event). For instance, the service agent can update thedata based on an automated analysis of past transactions (e.g., asdefined by signaling messages that pass to or through the service agentor by other information). Or subscribers could access and update theirparticular data (e.g., buddy lists) via a suitable provisioninginterface (e.g., via a web server that then provides updated data toservice agent 62, or through interaction with a customer serviceoperator) and/or via a mobile handset.

Alternatively or additionally, the data that the service agent makesavailable for use by the application server could be defined by a morestatic set of logic. For instance, logic 64 could include program codethat requires the service agent to publish a particular set of data inone instance (e.g., for one given communicating entity, applicationserver or communication service) and to publish another particular setof data in another instance (e.g., for a different communicating entity,application server or communication service).

Referring now to FIG. 4, a flow chart is provided to help illustrate howthe exemplary embodiment could function during initiation of a PTTsession in the arrangement shown in FIG. 3. As shown in FIG. 4, at block100, a user of MS 48 invokes a PTT application on MS 48. At block 102,the PTT application then responsively sends a SIP INVITE or othersignaling message to service agent 62. (For instance, the PTTapplication may invoke a SIP user agent application to send a suitableSIP INVITE). In the exemplary embodiment, the signaling messageidentifies MS 48 and/or the user as the source (communicating entity)and identifies the destination and/or type of communication as a PTTsession.

At block 104, service agent 62 then receives the signaling message andproceeds to parse and evaluate the message, noting that the message is aPTT initiation message from the designated communicating entity. Inturn, at block 106, service agent 62 queries data store 66 to extract agroup list that has been designated in advance for the communicatingentity. The group list might identify entities A, B and C as the membersof the communicating entity's group. Further, by querying a profilerecord for the communicating entity, service agent 62 may determine thatPTT server 68 (at a particular network address) has been designated tohandle PTT sessions for that communicating entity.

At block 108, service agent 62 then publishes the communicating entity'sgroup list in public store 74. For instance, service agent 62 may writethe group list to a suitably named file or database table in publicstore 74. Further, service agent 62 may insert into the signalingmessage a pointer to the data in public store 74. And at block 110,service agent 62 proxies the signaling message to PTT server 68.

At block 112, PTT server 68 then receives the signaling message anddetects that it is a request to initiate a PTT session for thedesignated communicating entity. Further, PTT server 68 notes that themessage points to the communicating entity's group list in public store74. Thus, at block 114, PTT server 68 then reads the group list frompublic store 74. And at block 116, PTT server 68 then sets up the PTTsession between the communicating entity and entities A, B and C.

Referring next to FIG. 5, another flow chart is now shown, to helpillustrate how the exemplary embodiment could function in multicastingof an instant message in the arrangement shown in FIG. 3. As shown atblock 200, a user of MS 48 invokes an IM application on MS 48 and entersan instant message to send to the user's group of buddies. At block 202,the IM application then responsively sends a SIP MESSAGE or othersignaling message to service agent 62. In the exemplary embodiment, thesignaling message identifies MS 48 and/or the user as the source(communicating entity), identifies the type of communication as amulticast instant message, and carries an ASCII text version of themessage entered by the user.

At block 204, service agent 62 then receives the signaling message andproceeds to parse and evaluate the message, noting that the message is amulticast instant message from the communicating entity. In turn, atblock 206, service agent 62 queries data store 66 to extract a grouplist that has been designated in advance for the communicating entity.For a multicast instant message from the communicating entity, thatgroup list might identify entities A and B as the members of thecommunicating entity's group.

At block 208, service agent 62 may then insert the group list into thesignaling message. For instance, the service agent may add an ASCII textversion of the group list directly into the message. And at block 210,the service agent may then proxy the signaling message to IM server 70.Thus, at block 212, IM server 70 receives the signaling message.

At block 214, after receipt of the signaling message, IM server 70 readsthe group list and message text from the signaling message. And, atblock 216, IM server 70 then responsively sends to entities A and B aninstant message containing the designated message text.

Finally, referring to FIG. 6, another flow chart is provided, to helpillustrate how the exemplary embodiment could function in facilitatingvoice mail service. As shown at block 300, a user of MS 48 invokes acommunication application on MS 48, seeking to establish a communicationsession over IP network 50 with a user who happens to be operatingentity B. Thus, at block 302, the communication application responsivelycauses a SIP user agent on MS 48 to send a SIP INVITE to service agent62, designating the user of MS 48 as the source and the user of entity Bas the destination.

When the service agent receives the SIP INVITE, the service agent thenidentifies entity B as the destination SIP user agent. Thus, at block304, the service agent then sends the INVITE to entity B. At block 306,a predefined timeout period expires with no response from entity B.Thus, the service agent determines that alternative processing of thesession request is required.

At block 308, the service agent then queries data store 66 to determinewhich VM server to use and to obtain any data that the service agentshould make available for use by that VM server to facilitate responseto the INVITE. For instance, the initiating user's profile may point toVM server 72 and may also point to a customized outgoing message audiofile stored in data store 66.

At block 310, the service agent may then publish the customized outgoingmessage audio file on a message bus for access by VM server 72. And atblock 312, the service agent may proxy the INVITE to VM server 72.

Upon receipt of the INVITE, at block 314, VM server 72 may then exchangefurther messages with the initiating SIP user agent, so as to establisha media session with MS 48. And, at block 316, VM server 72 may retrievethe customized outgoing message audio file from the message bus. Inturn, at block 318, VM server 72 may then play out the customizedoutgoing message to the initiating user, so as to prompt the initiatinguser to leave a voice mail message.

An exemplary embodiment of the present invention has been describedabove. It should be understood, however, that changes and modificationscan be made to this exemplary embodiment without departing from the truescope and spirit of the present invention, which is defined by theclaims.

For example, while the foregoing discussion focuses mainly on operationof an enhanced proxy server, the principles described can be extended touse with respect to an enhanced registration server. For instance, whena SIP user registers with a SIP registration server, the SIPregistration server may responsively extract from a data store a set ofdata particular to that SIP user and then make that data available foruse by an application server that may handle signaling messagesconcerning the SIP user. As noted above, the service agent might includea registration server. So a service agent may perform this function.

As a particular example, when a SIP user sends a SIP REGISTER message toa registration server on service agent 62, service agent 62 may thenresponsively query the user's profile and determine that the user is aPTT user (or that the user's device supports PTT service). In responseto that determination, the service agent may then extract the user'sbuddy list from data store 66 and publish that buddy list to publicstore 74. Thereafter, when PTT server 68 seeks to set up a PTT sessionfor the user, PTT server 68 can obtain the user's group list from publicstore 74 and use the group list to facilitate setting up the PTTsession.

We claim:
 1. A method comprising: receiving into a network entity asignaling message indicative of a call attempt from a calling party to acalled party; the network entity extracting from a data store anoutgoing media message playable by a voice mail server to the callingparty; and the network entity (i) outputting the signaling message fortransmission over a network to the voice mail server and (ii) making theoutgoing media message available for the voice mail server to play tothe calling party in a session established between the voice mail serverand the calling party in response to the signaling message, wherein theextracting is done in response to receiving the signaling message, andwherein extracting the outgoing media message from the data store inresponse to receiving the signaling message comprises (i) afterreceiving the signaling message, sending the signaling message to thecalled party and then determining that the called party does not respondand (ii) responsive to the determining, extracting the outgoing mediamessage from the data store.
 2. A method comprising: transporting aninitiation message over a radio access network from a wireless mobilestation to a packet-switched network, the initiation message beingindicative of a request from a user of the wireless mobile station toengage in a communication with a designated party; transmitting theinitiation message over the packet-switched network to a signaling proxyserver, and receiving the initiation message into the signaling proxyserver; the signaling proxy server sending the initiation message to thedesignated party and then determining that the designated party does notrespond; responsive to the determining, the signaling proxy serverextracting from a data store an outgoing voice mail message playable bya voice mail server to the wireless mobile station, and the signalingproxy server (i) forwarding the initiation message to the voice mailserver and (ii) making the outgoing voice mail message available for thevoice mail server to play to the wireless mobile station in a sessionestablished in response to the initiation message.
 3. The method ofclaim 2, further comprising: the voice mail server (i) receiving theinitiation message, (ii) establishing the session with the wirelessmobile station, and (iii) playing out the outgoing voice mail message tothe wireless mobile station in the session.
 4. The method of claim 2,wherein the outgoing voice mail message comprises an audio file.
 5. Themethod of claim 2, wherein the outgoing voice mail message is customizedfor the designated party.
 6. The method of claim 2, wherein theinitiation message comprises a Session Initiation Protocol (SIP) INVITEmessage.